SAN FRANCISCO — Dozens of friends and family members of slain Dodgers fan Jonathan Denver came together outside AT&T Park on Sunday before game time to pass out fliers seeking witnesses to the Wednesday night stabbing preceded by taunts of team rivalry.

Clutching one another for support, Denver's father, brother, mother and aunt also stood before a bank of cameras to make their plea and offer more personal details about the 24-year-old apprentice plumber from Fort Bragg, Calif., nicknamed "Burrito."

Robert Preece of Alhambra — Denver's father and a security supervisor at Dodger stadium — described losing a child as "a heartache no parent should have to endure."

In a nod to the family of the 21-year-old Lodi man who police said implicated himself in the stabbing but is said to be claiming self-defense, Preece said, "I also understand that the Montgomery family is likely suffering as well." He pleaded for any witnesses to contact authorities "so that both families can have some measure of closure."

Michael Montgomery was arrested after the incident and booked into San Francisco County Jail on Thursday afternoon. But Dist. Atty. George Gascon late Friday sent the case back to police for further investigation, saying more witnesses needed to be interviewed to support or rule out legally justified homicide.

Preece and his son, Robert, who was also at Sunday's news conference but declined to speak, are both witnesses to the stabbing. But they shed little light on what happened Wednesday night, when police say a "back and forth" over the Dodgers-Giants rivalry triggered two altercations between their group and Montgomery's.

Montgomery's group had come to the city to go to a club and did not attend the game that night, but a friend of Montgomery's was wearing a Giants hat, and Montgomery told his father that Denver, who was wearing Dodgers gear, yelled, "Giants suck!" He is said to contend that he stabbed Denver only after the Dodgers fan "jumped" him.

Preece declined to address Montgomery's contention of self-defense, saying he is "trusting that [police and prosecutors] are going to do what's right." Preece's sister, Jill Haro, said: "This is why we're here today. We're looking for the public's help. We have reason to believe people may have [recorded] it and witnessed it, and we need them to come forward."

The family chose instead to focus on the young man they loved and lost. Preece, choking back tears, said he would always remember Wednesday night's game, which he attended with his two sons in a belated celebration of his 49th birthday.

"More than once that night, Jonathan told me how much he loved me," Preece said. "That will remain a most cherished memory for me."

Denver's mother, Diana Denver of Fort Bragg, spoke briefly, criticizing the media for "maligning my son's character," presumably by reporting on drunk-driving and public-intoxication arrests. "Remember, he was the victim," she said.

She also criticized the criminal-justice system for releasing Montgomery without charges.

But mostly, she spoke to her son's character, saying he was "well known and loved in his community" and describing him as "loving, caring and kind. His laughter was everything, and what a smile he had," she said.

Denver, who went by Jon (as well as Burrito), loved his dogs, Buster and Blue, and adored his brother, Robert, who was his roommate and dear friend, she said.

Sunday's group — more than 40 people from Fort Bragg and several dozen from the Southland — began arriving Saturday evening in San Francisco to pass out fliers. Some wore blue sweat shirts emblazoned with "RIP Jon D."

"We need your help," says one handout, with a photo of Preece and his sons at Wednesday's game.

"The SFPD and district attorney's office are seeking additional independent evidence regarding the death of our friend and family member Jonathan Denver," it reads, asking anyone with information that "can help bring forth the truth" to contact either agency.

Sharon Rocco, a 62-year-old retired parole agent and avid Giants fan, was heading into the ballpark Sunday as reporters gathered for the family's news conference.

"What is very sad is I think we've had an evolution of aggressiveness," she said. "We've lost the ability to respect other people's beliefs." The crux of the fight may have been Giants-Dodgers rivalry, she said, "but they just lost self control."